From patchwork Thu Dec 9 17:08:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 522800 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 12BB9C433EF for ; Thu, 9 Dec 2021 17:08:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242445AbhLIRMT (ORCPT ); Thu, 9 Dec 2021 12:12:19 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:21864 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239053AbhLIRLz (ORCPT ); Thu, 9 Dec 2021 12:11:55 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1639069701; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=U+HuoVKpu95c2SdU4PtFRJoEoWn1fNPxJawKKDa63+k=; b=K5529dtUDZ4U4fa06a7F7rXvKvPbZmdTnpJKKKIaVxJGw1P+nK8ooaepoiw/gRNmo6UXje +nIRmun/snRlPPdyePN+kfvGxYHUfh+zy7W0//+sASWO2bDw5z9bzneA2gZb4epcV5FZaO ZKfwN5RwTBnyV6EGvJaJ3VJ6qKD+qGY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-516-1YcpFrybPmeB5137idmN6g-1; Thu, 09 Dec 2021 12:08:16 -0500 X-MC-Unique: 1YcpFrybPmeB5137idmN6g-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C59221006AA1; Thu, 9 Dec 2021 17:08:14 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.122]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3A8035C23A; Thu, 9 Dec 2021 17:08:07 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH v2 56/67] afs: Fix afs_write_end() to handle len > page size From: David Howells To: linux-cachefs@redhat.com Cc: Jeff Layton , Jeff Layton , Marc Dionne , Al Viro , Matthew Wilcox , linux-afs@lists.infradead.org, dhowells@redhat.com, Trond Myklebust , Anna Schumaker , Steve French , Dominique Martinet , Jeff Layton , Matthew Wilcox , Alexander Viro , Omar Sandoval , JeffleXu , Linus Torvalds , linux-afs@lists.infradead.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, v9fs-developer@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Thu, 09 Dec 2021 17:08:06 +0000 Message-ID: <163906968632.143852.17508469800625963114.stgit@warthog.procyon.org.uk> In-Reply-To: <163906878733.143852.5604115678965006622.stgit@warthog.procyon.org.uk> References: <163906878733.143852.5604115678965006622.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org It is possible for the len argument to afs_write_end() to overrun the end of the page (len is used to key the size of the page in afs_write_start() when compound pages become a regular thing). Fix afs_write_end() to correctly trim the write length so that it doesn't exceed the end of the page. Fixes: 3003bbd0697b ("afs: Use the netfs_write_begin() helper") Reported-by: Jeff Layton Signed-off-by: David Howells Acked-by: Jeff Layton cc: Marc Dionne cc: Al Viro cc: Matthew Wilcox cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/162367682522.460125.5652091227576721609.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/163819660464.215744.4576104569408497052.stgit@warthog.procyon.org.uk/ # v1 --- fs/afs/write.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/afs/write.c b/fs/afs/write.c index 8e4e87d66855..9db3ddb1c45b 100644 --- a/fs/afs/write.c +++ b/fs/afs/write.c @@ -120,6 +120,7 @@ int afs_write_end(struct file *file, struct address_space *mapping, _enter("{%llx:%llu},{%lx}", vnode->fid.vid, vnode->fid.vnode, folio_index(folio)); + len = min_t(size_t, len, folio_size(folio) - from); if (!folio_test_uptodate(folio)) { if (copied < len) { copied = 0;